CVE-2026-87022 Security Details

CVE ID

CVE-2026-87022

CWE

CWE-130

CVE Description

Improper handling of length parameter inconsistency vulnerability in Apache Tomcat allows WebSocket message smuggling when per-message-deflate is used. This issue affects Apache Tomcat: from 11.0.0-M1 through 11.0.25, from 10.1.0-M1 through 10.1.59, from 9.0.0.M1 through 9.0.121. The following versions were EOS at the time the CVE was created but are known to be affected: from 8.5.0 through 8.5.100, from 7.0.56 through 7.0.109. Other unsupported versions may also be affected. Users are recommended to upgrade to version 11.0.26, 10.1.60 or 9.1.22, which fix the issue.

Published

Sep 24, 2026

CVSS Score & Severity

8.7High

CVSS Vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

EPSS Score

0.540%

Malware

malware

KEV Status

Not in KEV Catalog: No known exploits

Vulnerable Methods

org/apache/tomcat/websocket/PerMessageDeflate.endFrame(Z)Lorg/apache/tomcat/websocket/TransformationResult;

JVM

org/apache/tomcat/websocket/PerMessageDeflate.getMoreData(BZILjava/nio/ByteBuffer;)Lorg/apache/tomcat/websocket/TransformationResult;

JVM

org/apache/tomcat/websocket/PerMessageDeflate.inflate([BII)I

JVM

Affected Ecosystems

affected

Source

National Vulnerability Database

References

Apache · AnnouncementPROJECT

Apache · Security advisoryPROJECT